Init repo with original content

.gitignore

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+target
+Cargo.lock
+.DS_Store
+._.DS_Store
+.VSCodeCounter

Cargo.toml

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+[package]
+name = "be-technical-interview-rust"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+regex = "1.10.4"
+chrono = "0.4"

README.md

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-# be-technical-interview-rust
+# Backend internal interview (rust)
 
-Backend internal interview (Rust)
+A **Refactor metric-consumer** task
+
+[Home Task exercise description](Home-Task_exercise_interview_Rust.pdf)
+
+There are several branches developed as proposal:
+
+- [Basic fixed one](basic-fixed)
+  > A basic code review, fixed with minor and essential changes to work as expected.
+  > Tests are included for verification.
+
+- [Improve one](improved)
+
+- [Multiple input one](multi-input)

input.txt

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+1650973075 cpu 47
+1650973087 cpu 47
+1650973099 mem 737917
+1650973111 cpu 50
+1650973123 cpu 49
+1650973135 cpu 49
+1650973147 mem 1761992
+1650973159 cpu 49
+1650973171 mem 1858502
+1650973183 cpu 51
+1650973195 cpu 55
+1650973207 mem 1076203
+1650973219 cpu 60
+1650973231 mem 640005
+1650973243 mem 324911
+1650973255 mem 1024
+1650973267 cpu 56
+1650973279 cpu 58
+1650973291 mem 1024
+1650973303 mem 1024
+1650973315 mem 1024
+1650973327 mem 1024
+1650973339 cpu 49
+1650973351 mem 1024
+1650973363 cpu 49

output_expected.txt

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+2022-04-26T11:37:00Z cpu 47.0
+2022-04-26T11:38:00Z cpu 48.75
+2022-04-26T11:39:00Z cpu 51.666666666666664
+2022-04-26T11:40:00Z cpu 60.0
+2022-04-26T11:41:00Z cpu 57.0
+2022-04-26T11:42:00Z cpu 49.0
+2022-04-26T11:38:00Z mem 737917.0
+2022-04-26T11:39:00Z mem 1810247.0
+2022-04-26T11:40:00Z mem 510535.75
+2022-04-26T11:41:00Z mem 1024.0
+2022-04-26T11:42:00Z mem 1024.0

src/main.rs

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+use std::collections::HashMap;
+use std::error::Error;
+use std::fs::File;
+use std::io::Read;
+use std::time::{Duration, UNIX_EPOCH};
+
+fn parse(
+    file: File,
+) -> Result<HashMap<String, HashMap<std::time::SystemTime, f64>>, Box<dyn Error>> {
+    let mut file = file;
+    let mut contents = String::new();
+    file.read_to_string(&mut contents)?;
+
+    let mut metrics: HashMap<String, HashMap<std::time::SystemTime, Vec<f64>>> = HashMap::new();
+
+    for line in contents.lines() {
+        let re = regex::Regex::new(r"(\d+) (\w+) (\d+)").unwrap();
+        if let Some(caps) = re.captures(line) {
+            let timestamp_raw = &caps[1];
+            let metric_name = &caps[2];
+            let metric_value_raw = &caps[3];
+
+            let timestamp = timestamp_raw.parse::<i64>().unwrap();
+            let metric_value = metric_value_raw.parse::<f64>().unwrap();
+
+            if !metrics.contains_key(metric_name) {
+                metrics.insert(metric_name.to_string(), HashMap::new());
+            }
+
+            let minute = UNIX_EPOCH + Duration::from_secs((timestamp - (timestamp % 60)) as u64);
+            metrics
+                .get_mut(metric_name)
+                .unwrap()
+                .insert(minute, vec![metric_value]);
+        } else {
+            println!("invalid line");
+        }
+    }
+
+    let mut aggregated_metrics: HashMap<String, HashMap<std::time::SystemTime, f64>> =
+        HashMap::new();
+
+    for (metric_name, time_val_list) in metrics {
+        aggregated_metrics.insert(metric_name.clone(), HashMap::new());
+
+        for (time, values) in time_val_list {
+            let mut sum = 0.0;
+            for v in values.iter() {
+                sum += *v
+            }
+            let average = sum / values.len() as f64;
+
+            aggregated_metrics
+                .get_mut(&metric_name)
+                .unwrap()
+                .insert(time, average);
+        }
+    }
+
+    Ok(aggregated_metrics)
+}
+
+fn main() {
+    let file = File::open("input.txt").expect("Unable to open file");
+    let metrics = parse(file).expect("Unable to parse file");
+    for (metric_name, time_val) in metrics {
+        for (time, value) in time_val {
+            println!(
+                "{} {:?} {:.2}",
+                metric_name,
+                chrono::DateTime::<chrono::Utc>::from(time),
+                value
+            );
+        }
+    }
+}